SiLabs breaks low-power record for touch-sense microcontrollers

PORTLAND, Ore. — Silicon Laboratories Inc. (Austin, Texas) claims to
have broken its own record for the industry's lowest power touch-sense
microcontrollers with its new F9xx family, promising to extend the
battery life of mobile devices at a lower cost than for previous
entries.

"To reduce the cost of the microcontroller by about 20 percent, we reduced its flashmemory
size and removed the dc/dc converter that enabled operation from a
single 1.5-volt battery," said Shahram Tadayon, MCU product marketing
manager at Silicon Labs. "The new devices operate at full speed all the
way down to 1.8 V and are still ultralow-power like before, but now
they also have a much lower price plus can fit into a smaller, 3 x 3-mm
package."

Maintaining a 150-microamp/MHz operation (down from the previous record of 160 microamps)
by virtue of an integrated low-dropout (LDO) regulator, the new family
also claims to offer the industry's lowest power in both active and
sleep modes, as well as enabling touch-to-awaken functions. The
microcontrollers can manage 14 touch-sensitive user interfaces on
consumer and industrial devices, ranging from home appliances to smart
meters, security systems, lighting, games and toys.

Silicon Labs provides its QuickSense library of common touchpad software
routines for quickly prototyping and deploying capacitive
touch-sensitive user interfaces. A patented capacitance-to-digital
converter (CDC) is said to enable a 40-microsecond acquisition time.
The sensitive CDC also supports proximity sensing for
recognizing human gestures in addition to button, slider and
rotary-knob emulation.

The touch-sense microcontrollers operate at up to 25 MHz using an 8051 core alongside a 12 bit analog-to-digital converter, temperature sensor, voltage reference, four timers and 2 to 8 kbytes of flash. They are priced at less than $1 in volume.